This invention relates to a cleaning tank and, particularly, to a construction of a cleaning tank utilized for cleaning a wafer and the like in producing a semi-conductor device, but the invention is not limited thereto. Various types of cleaning tanks have been utilized for cleaning a wafer and the like in producing a semi-conductor device. However, such prior art cleaning tanks cannot attain uniform flow of cleaning liquid in the cleaning tank and, reverse flow or turbulent flow has been observed in the cleaning tank. Thus, the cleaning liquid passed through the article to be cleaned and contaminated or bearing the substance removed from the surface of the article to be cleaned may mix with the fresh cleaning liquid, which decrease the cleaning efficiency substantially. Therefore, it has highly been required to provide a cleaning tank which can attain uniform liquid flow through every location in the cleaning tank.
An object of the present invention is to provide a novel cleaning tank having excellent cleaning characteristics.